Certain disease states require and/or benefit from treatment using one or more different drug agents (i.e., combination therapy). For example, in some cases it might be beneficial to treat a diabetic with a long-acting insulin and with a glucagon-like peptide-1 (GLP-1), which is derived from the transcription product of the proglucagon gene. GLP-1 is found in the body and is secreted by the intestinal L cell as a gut hormone. GLP-1 possesses several physiological properties that make it (and its analogs) a subject of intensive investigation as a potential treatment of diabetes mellitus. Although combination therapy may be preferred in some cases, some drug agents need to be delivered in a specific relationship with each other in order to deliver the optimum therapeutic dose. The disclosed system and corresponding method is of particular benefit where combination therapy is desirable, but not possible in a single medicament formulation for reasons such as, but not limited to, stability, compromised therapeutic performance, and toxicology.
There are a number of potential problems associated with the storage and delivery of two active drug agents. For instance, the two active drug agents may interact with each other during long-term storage. Therefore, it is advantageous to store the active drug agents separately and only combine them at the point of delivery via injection, needle-less injection, pumps, or inhalation. However, the process for combining the two active drug agents needs to be simple and convenient for the user to perform reliably, repeatedly, and safely.
A further problem is that the quantities and/or proportions of each active drug agent making up the combination therapy may need to be varied for each user or at different stages of their therapy. For example, certain active drug agents may require a titration period to gradually introduce a user to a “maintenance” dose. A further example would be if one active drug agent requires a non-adjustable fixed dose while the other is varied in response to a user's symptoms or physical condition. This problem means that pre-mixed medicament formulations of multiple active drug agents may not be suitable as these pre-mixed formulations would have a fixed ratio of the active drug agents, which could not be varied by the healthcare professional or user.
Additionally, many users cannot cope with having to use more than one drug delivery system or having to make the necessary accurate calculation of the required dose combination. This is especially true for users with dexterity or computational difficulties. Accordingly, there exists a strong need to provide systems and methods for the delivery of two or more drug agents that is simple for the user to perform.
The disclosed system and corresponding method helps overcome the above-mentioned problems by providing separate reservoirs for the two or more drug agents making up the desired combination therapy. The two or more active drug agents are only combined and/or delivered to the user at delivery. Thus, the two or more active drug agents will not interact with each other during long-term storage. Further, the disclosed system and corresponding method is capable of achieving a wide variety of therapeutic dose profiles, therefore, making combination therapy that may need to be varied for each user or at different stages of their therapy possible.
These and other advantages will become evident from the following more detailed description of the invention.